Field of the Invention
The present invention relates generally to the field of surgical procedures, and more specifically to the enhanced control of medical devices such as foot pedals and switches used in surgical procedures.
Description of the Related Art
Ocular surgical procedures include phacoemulsification, diathermy, and vitrectomy procedures.
Phacoemulsification refers to a method of lens and cataract extraction from an eye. The procedure includes an ultrasonically vibrated needle which is inserted through a very small incision in the cornea in order to provide energy for emulsifying or breaking up of the lens and cataract which then can be aspirated and removed through the incision.
Diathermy refers to a method of cautery to seal severed or ruptured blood vessels. Diathermy is used in ophthalmic surgery to halt bleeding associated with surgical incisions
Vitrectomy surgery has been successfully employed during cataract surgery when the posterior capsular bag has been broken and in the treatment of retinal detachments resulting from tears or holes in the retina. In cataract surgery, the same incision used for the phacoemulsification handpiece is used for inserting the vitrector to remove the vitreous gel. Vitrectomy surgery typically involves removal of vitreous gel and may utilize three small incisions in the pars plana of the patient's eye. These incisions allow the surgeon to pass three separate instruments into the patient's eye to affect the ocular procedure. The surgical instruments typically include a vitreous cutting device, an illumination source, and an infusion port.
Phacoemulsification and vitrectomy procedures may require fluid control, namely control over aspiration and irrigation to the ocular region, and employ a handpiece that is typically electrically driven and must be controlled. As the surgeon is employing the handpiece and possibly a fluid handpiece during surgery, control is provided to the surgeon via a foot pedal. Foot pedals vary in design, but more modern foot pedals include a treadle that can be moved in a fore-and-aft direction (a pitch motion) and in a left-and-right direction (a yaw motion). Hard switches are also provided, where the switches typically provide a toggle functionality and/or an on-off functionality. Control can be provided for various device components and operations for the phacoemulsification, diathermy or vitrectomy machine, including control of fluid flow, entry into various modes, electrical parameters, speed parameters (e.g. cut speed), and so forth.
One of the issues with traditional foot pedals is the dexterity required to perform multiple foot pedal operations, i.e. engage the foot pedal at multiple positions or to perform more than one function. For example, a surgeon may be controlling fluid flow using movement of the treadle in the pitch and yaw axes, attaining a certain position to achieve desired fluid flow balance, and may then need to engage a switch to raise or lower the height of an irrigation source, such as an irrigation bottle. It can be difficult to maintain the desired level of fluid flow, i.e. maintain the desired treadle position, and at the same time engage a footswitch without either disrupting fluid flow or altering fluid flow and subsequently attempting to reacquire the same fluid flow state in this example. Foot pedal switches have been offered at different positions on different foot pedals, but generally are located proximate the treadle, such as at the sides, near the base, or at the forward tip of the treadle. In certain foot pedal designs, top switches are provided that are on the underside of the top of an enclosed foot pedal.
Such foot pedal switches may be electromechanical, and such switches tend to increase the cost and complexity of foot pedal design, and have an increased chance of failure. As with any device having multiple components, failure of one component can result in the device being unusable in its entirety, and loss of a foot pedal or any of its functions can be highly problematic.
Further, existing foot pedal switches can be sensitive and at times inaccurate as far as detection of engagement. Certain transient or inadvertent physical actions may be considered switch engagements when in actuality they are nothing more than spurious events. Such sensitivities are undesirable and should be minimized.
Based on the foregoing, it would be advantageous to provide a foot pedal design that limits the need for foot pedal switch functionality, and/or provides an ability to distinguish engagement of a foot pedal switch from an inadvertent transient or momentary occurrence. Such a design would afford a surgeon the ability to engage desired phacoemulsification, diathermy, or vitrectomy functions with less need to employ foot pedal switches, and/or obtain better performance from foot pedal switches.